This proposal requests funds for a Seahorse XF96e Metabolic Analyzer. The system will be housed in the Small Molecules Screening and Synthesis Facility at the Wisconsin Institutes for Medical Research in the University of Wisconsin Carbone Cancer Center (UWCCC). It will be available for members of the UWCCC, and more widely, for researchers in the UW Hospital and Pharmacy buildings. Although there have been some 600 Analyzers sold nation-wide to date, this will be the first analyzer to come to the University of Wisconsin School of Medicine and Public Health campus. It represents a unique instrument with the potential to complement or replace the assays that are currently run in our biomedical research labs. This analyzer generates detailed information about the relative rates of glycolysis and oxidative phosphorylation, either at equilibrium, or after perturbation of live cell systems. With the re-emergence of metabolism as a key regulator of growth, not only of tumors, but stem cell populations, this instrument will be key to the interpretation of their phenotypes.